Passthru NixOS system & OpenGL Driver

Signed-off-by: Tristan Ross <[email protected]>

crates/krun-guest/src/mount.rs

@@ -1,9 +1,10 @@
-use std::fs::File;
+use std::fs::{File, create_dir_all};
+use std::env::var_os;
 use std::os::fd::AsFd;
 
 use anyhow::{Context, Result};
 use rustix::fs::CWD;
-use rustix::mount::{mount2, move_mount, open_tree, MountFlags, MoveMountFlags, OpenTreeFlags};
+use rustix::mount::{mount2, move_mount, mount_recursive_bind, open_tree, MountFlags, MoveMountFlags, OpenTreeFlags};
 
 pub fn mount_filesystems() -> Result<()> {
     mount2(
@@ -40,6 +41,26 @@ pub fn mount_filesystems() -> Result<()> {
         .context("Failed to move_mount `/etc/resolv.conf`")?;
     }
 
+    let opengl_driver = var_os("OPENGL_DRIVER");
+    if let Some(dir) = opengl_driver {
+        create_dir_all("/run/opengl-driver")?;
+        mount_recursive_bind(
+            dir,
+            "/run/opengl-driver",
+        )
+        .context("Failed to mount `/run/opengl-driver`")?;
+    }
+
+    let nixos_curr_sys = var_os("NIXOS_CURRENT_SYSTEM");
+    if let Some(dir) = nixos_curr_sys {
+        create_dir_all("/run/current-system")?;
+        mount_recursive_bind(
+            dir,
+            "/run/current-system",
+        )
+        .context("Failed to mount `/run/current-system`")?;
+    }
+
     mount2(
         Some("binfmt_misc"),
         "/proc/sys/fs/binfmt_misc",

crates/krun/src/env.rs

@@ -17,6 +17,8 @@ const WELL_KNOWN_ENV_VARS: [&str; 5] = [
     "MESA_LOADER_DRIVER_OVERRIDE", // needed for asahi
     "PATH",                        // needed by `krun-guest` program
     "RUST_LOG",
+    "OPENGL_DRIVER",               // needed for OpenGL on NixOS
+    "NIXOS_CURRENT_SYSTEM",        // needed for some paths to work on NixOS
 ];
 
 /// See https://github.com/AsahiLinux/docs/wiki/Devices